The invention relates to a method for operating a redundant, ringlike communications network and to a communications network which makes use of this method.
From the prior art, ringlike communications networks with redundant function, which have a primary participant or “master” and secondary participants or “slaves” are known.
German Patent Application DE 10 2004 041 093 describes one such ringlike communications network in FIG. 1a, which could for instance represent a control and drive system for shaftless production machines. Such systems utilize a so-called bidirectional double ring for communication. In the redundant case (error case), the double ring falls apart into two line topologies. Communication between secondary stations that are not affected by the malfunction then takes place solely by the recopying, via the main station, of all the data sent by secondary participants. This increases the load on the main station considerably and causes runtime delays between directly adjacent secondary participants.